Apparatus for equalizing the tension of threads



Nam 9, 1937 R. s. FRANCIS 2,@98,413

APPARATUS FOR EQUALIZING THE TENSION OF THREADS Filed May 12, 1936 2 Sheets-Sheet 1 A ORNEY.

Nov. g, 37. A R s. FRANCIS y fi APPARATUS FOR EQUALIZING THE TENSION OF THREADS Filed May 12, 1936 2 Sheets-Shet 2 Y BY f ATTORNEY.

Patented Novn 9, 19 37 UNITED S ATES PATENT OFFICE APPARATUS FOR EQUALIZING 'THE TEN- .SION 0F THREADS Raymond 8. Francis, Bumiord, B. 1., assignor to United States Rubber Products, Inc., New- Yorlr, N. Y., a corporation of Delaware Application y 12, 1936, Serial n. 19,255

ric.

It is found dimcult in practice to draw a number of rubber threads from spools or other sources of supply so'that they will be under uniform tension. This is due in part to the tendency of elastic threads to change their tension over a period of time when stored upon a beam or spool, and also to the fact that the rubber threads when wound upon a spool or beam tend to sink into and cling to the underlying coils, so that if rubber threads are drawn from a number of spools they will unwind more freely from some spools than others.

Therefore, in warping rubber threads heretofore it was found that if all of the supply spools were rotated at the same speed in unwinding the rubber threads therefrom a larger variation in the tension of these threads when arranged in a warp chain would result. In order to balance or equalire the tension of the rubber threads it has been the practice heretofore of unwinding these threads from their source of supply onto a long table. They are then divided while on the table into warps of the desired number of ends and are balanced by a hand operation of raising and lowering the warp and. separating the threads thereof withthe fingers along the table so that the threads may be freed of tension and placed in a balanced condition, after which the group of threads may be chain-looped or coiled back and forth in acontainer.

The present invention contemplates power bperated mechanisms for balancing and equalizin the tension of elastic threads as they are drawn from their source of supply without requiring the hand balancing method employed heretofore, and while the present invention was developed more 5 particularly for use in equalizing the tension of elastic threads, it may be used to equalize the tension of inelastic threads.

-An important feature of the present invention resides in power driven tension regulating rolls about which the threads being drawn from the sources of supply are looped so that the slack or taut condition of each thread will control its frictional engagement with the rolls and thereby control the forward pull to which it is subjected by these rolls.

Another feature of the invention resides in means for supporting one of said power driven rolls for angular adjustment about the other roll to thereby vary the frictional engagement between the threads and the rolls about which they are looped, and a further feature resides in manually controlled locked means for facilitating the an- I gular adjustment of one of said rolls and in the locking of'this roll in the desired position.

Still a further feature resides in the construction and arrangement whereby said adjustable roll may be swung to an inoperative position'to facilitate the free passage of the threads between said roll when the machine is being threaded up.

The above and other features of the invention I and novel combination of parts will be further understood from the following description and accompanying drawings which illustrate one good practical form thereof.

In the drawings:

Figure l is a side elevation of the machine constructed in accordance with the present invention;

Figure 2 is a top plan view of the machine of Fig.1;

- Figure 3 on a larger scale is a sectional view taken on the line 8-3 of Fig. 1;

Figure 4 is a diagrammatic side elevation of the thread balancing mechanism of .the invention;

Figure 5 is a transverse sectional view through the pull rolls of Fig. 3, these rolls being shown in their threading up position; and

Figure 6 is a sectional view taken on the line as or 3. v

The operating parts of the machine in the construction shown are supported by the spaced upright channels it which are provided at their lower ends with the supporting feet ii that maybe bolted to the floor. These uprights are rigidly supported in spaced relation to each other by the cross braces i2.

The uprights Ill serve to support at the desired height from the floor a pair of cooperating pull rolls or tension regulating rolls i3 and it, and in the construction shown one of these rolls I4 is supported for movement bodily in the arc of a circle about the longitudinal axis of the other roll it, as shown in Figs. 5 and 6. This angular ad- Justment of the roll it about the axis of the roll i3 serves to increase or decrease the friction pulling action upon the threads to be described, as

present will be apparent in Fig. 6, and also serves to permit the movement of the roll I4 downwardly below the roll I3 to facilitate threading up of the threads as will be apparent from Fig. 5. While it is highly desirable to support one roll for angular adjustment relative to the other roll for the purposes just mentioned, this is not essential in all embodiments of the invention since the present apparatus may be employed to equalize the tension of threads if one roll is permanently supported above the other so that the threads the tension of which is to be equalized may be looped in one direction about one roll and in the opposite direction about the other roll.

The mechanism of the present invention may be employed to equalize the tension of either elastic or inelastic threads but is designed more particularly for use in equalizing the tension of bare rubber threads or covered elastic threads. These threads T may be supplied to the tension equalizing mechanism of the present invention from the individual spools I5 which spools may be supported upon a creel, rack or stand I6 and in practice it is found desirable to provide the spools I5 with supporting trunnions, not shown, but which may be journalled in wooden bearing blocks so that the spools may rotate freely as the threads T are withdrawn therefrom but will not overrun. In the construction shown the various threads T supplied by the spools I5 are led over a spacing comb I! having the teeth I8 adapted to separate the threadsand prevent them from becoming tangled. It is desirable to provide a considerable space between the spools I5 and the comb I? such forexample as a distance of 20 feet to facilitate the equalizing of the tension of each .thread throughout a substantial length thereof as it is unwound from its spool.

The comb il in the construction shown is supported in spaced relation to the uprights I8 by the arms I9 secured to the upper portion of these uprights and when the machine is in operation the threads T pass in a general horizontal direction through the teeth of the comb and are looped about the upper roll I4 in one direction and about the lower roll I3 in the opposite direction as best shown in Fig. 6. It is desirable to provide means for holding these threads looped about the lower roll I3 so that each thread is free to sag away from this roll as it becomes slack and embraces this roll to be pulled forward thereby as it becomes taut. The means shown for supporting these threads looped about the lower roll comprises the bar 20 which extends transversely of the machine throughout its width and this bar in accordance with the present invention is provided near its ends with the laterally extending arms 2I which are pivotally secured to the supports 22 that project materially from the uprights II]. The construction is such that the thread supporting bar 20 may occupy the position in which it is shown in Fig. 5 during the threading up operation, and during the operation of the machine to equalize the tension of the threads this bar 2I occupies the raised position in whiohvit is shown in Fig. 6. The arms 2I at the opposite ends of this bar serve to support it so that it may be swung through the arc of a circle from its lower position of Fig. 5 to its raised position of Fig. 6 and in the latter position it may rest against the uprights III to thereby maintain this bar spaced the desired distance from the roll I3.

The function of the rolls I3 and I4 is to frictionally pull each thread T forward independently of the tension of the other threads and to accomplish this the rolls I3 and I4 are driven at a speed considerably in excess of the maximum speed at which the threads T are to be supplied to the takeup means to be described. These two rolls may be driven at the same speed, or the roll I3 which in the present case is shown as larger in diameter than the roll I4 may be driven at either a faster or slower surface speed than the roll I4. The threads T upon leaving the tension regulating mechanism shown in Figs. 5 and 6 may be drawn along a relatively long table or supporting surface 23 and may then pass between the cooperating feed rolls 24 which serve to pull the threads forwardly at a uniform rate of travel over the surface of the table 23 and to deliver these threads in the form of warp threads in a well balanced condition with their tension equalized, whereupon they may be wound upon a warp beam or they may be chain-looped or coiled back and forth in a container.

It is desirable that pull rolls I3 and I4 have a smooth and accurately formed cylindrical surface and the roll I3 in the construction shown comprises a tube of steel having a highly polished outer surface which may be chrome plated and this tube has rigidly secured in one end thereof the supporting head 25 which head is provided with a central hub or boss 26 and rigidly secured in the opposite end of this tube is the head 21 having a similar central boss 26. The roll I3 thus formed is rigidly secured to a central supporting shaft 28 and the heads 25 and 2'! may be secured to this shaft by the pins 29. The shaft 28 has rigidly secured to one end thereof the driving pulley 38.

The roll I4, as above stated, is preferably so supported that it may be swung through the arc of a circle about the axis of the roll I3 and the means of the present invention for supporting the roll I 4 for this swinging movement will now be described. Each upright I 0 is provided near its upper end with a hole or opening in which is rigidly mounted a bearing sleeve 3|. These sleeves 3I serve to pivotally mount the brackets or castings 32 and 33 which serve to swingingly support the roll I4. To this end each of these brackets is provided with a hub 34 adapted to be journalled in the bore of the sleeve 3I. Within each hub 34 in. the construction shown is mounted a ball or anti-friction bearing 35 which is adapted to rotatably support the shaft 28 with in the hubs of the brackets 32 and 33.

' ;The bracket 32 is provided near its outer end with a boss 36 and the bracket 33 is provided with a similar boss 31. Within these aligned bosses 36 and 31 is mounted a shaft 38 which serves to rotatably support the roll I4. This roll as shown is formed of a highly polished steel tube like the roll I3 and has rigidly mounted in one end thereof the head 39 and in the opposite end thereof. the head 40. The roll I4 is rotatably supported upon the shaft 38 by the ball or antifriction bearings H. The shaft 38 is preferably provided near each end thereof with a shoulder adapted to form abutments for the inner faces of the bosses 36 and 31 so that the .ends of the shaft 38 may be rigidly clamped'within these bosses by tightening up the nuts 42 at the outer ends of the shaft 38. As a result of this construction the brackets 32 and 33 are rigidly clamped in spaced relation to each other and serve to rotatably support both rolls I3 and I4 and also support the latter roll for swinging movement about the axis of the roll I3 in the are of a circle indicated by a: in Figs. and 6. The weight of the roll it is preferably counterbalanced by bolting to the castings 32. and 33 the counter-balancing weights 3.

5 The roll it is driven by the pulley above mentioned and the roll in the construction shown is driven by providing the roll l3 at one end thereof, inside the casing 33, with a gear 44 whichis-bolted or otherwise secured to the head 10 21. This gear may be formed of fiber or other non-metallic material and meshes with a gear which maybe bolted to or formed integrally with the head flu provided in one end of the tube formor gear til and upon each upright it is slidably.

mounted a bolt it adapted to cooperate with the teeth of the rings 41 to lock the swinging brackets 32 and 33 in any desired position of angular adjustment. 4 I

The bolts tit are slidably mounted in the guide- Lways (it and .each bolt is continuously urged to its locking position by a coiled spring 5d surrounding the bolt and confined between a shoulder 5i upon the bolt and a guide block 52 rigidly secured to the upright. It is desirable to provide means whereby the 'bolts id may be manually retracted from either side of the machine. This is accomplished in the construction shown by providing the operating shaft 53 supported by the uprights it for rocking movement, and projecting laterally from this shaft adjacent its endsare the'operating handles 56. The shaft is also provided at each end thereof with an operating 5 arm 55 and extending upwardly from each arm 55 to a locking bolt id is a connecting rod 56. The arrangementis such that both bolts 58 may be retracted simultaneously by pressing upon the operating lever 56 at either side of the machine to move the same in a clockwise direction, viewed as in Fig. 1. r I

In the construction" shown the pulley 38 is driven by a belt 5? by an electric motor 58 and the proper tension is maintained upon this belt in the construction shown by floatingly mounting the motor so that'the weight of this motor will serve to tension the belt. To this end in the construction shown a pair of motor supporting brackets 59 are provided which are bolted to the transverse braces it in spaced relation to each other and these brackets are connected by the shaft td upon which are swinginglymounted the motor supporting arms 8i. The motor casing is bolted upon the swinging arms and the armature shaft of the motor [projects through an elongated slot d2 formed in an upright in and mounted upon this armature shaft at the outer face of the upright in is the belt driving pulley at. f

The operation of-the present machine is as follows, when it is desired to thread up the present machine ready to start operation, the roll it is swung downwardly to the approximate position in which it is shown in Fig. 5. The various threads T are thenled from the supply spools 65 over the comb i'l so that they are separated teeth of the comb and then downwardly by the the rolls l3 and I4 and over the bar 2! 75 between as shown in Fig. 5. The roll it is then swung upwardly to the position in which it is shown in section in Fig. 6 or if a less degree of pulling tension is desired, to one of the positions indicated in dot-and dash lines of Fig. 6. The other sup- 5 porting bar 20 is then swung upwardly from the position in which it is shown in Fig. 5 to its operating position of Fig. 6.' The adjustments just described serve to loop the threads about the upper roll l4 in'one direction and about the lower roll I3 in the opposite direction and these threads are held looped about the lower roll 53 by the supporting bar 20. The threads lying upon the table or supporting surface 23 are drawn forward by the feed rolls 24 'and this will tend to tension the threads where they are looped about the lower side of the pull roll it. Any'tensioning of these threafds at this point will cause them to move from the full line position indicated by a in Fig. 6 to the dotted line position indicated by b or c to thereby increase the pulling action which the rolls l3 and I4 will exert upon the threads T to draw them forward from their, source of supply l5. As a result of this construction the rate at which each thread T is pulled forward from its source of supply by the rolls iii and it will be controlled by the taut or slack condition of this thread about the lower side of the roll it and if the rolls l8 and it are driven at a surface speed at least 75% in excess of the maximum amount required to take care of the stretch of the elastic threads and their normal rate of delivery all threads will be delivered at the nip of the feed rolls 26 under uniform tension irrespective of the tension to which they may be subjected at the time they leave the supply spools it. i

Having thus described my invention what I claim and desire to protect by Letters Patent is:

1. In a machine of the-class described, in combination, mechanism for drawing forward simultaneously a number of threads, means for equalizing the tension of the individual threads supplied to said mechanism, including a pair of power driven tension regulating rolls spaced apart to provide a free passage for the threads therebetween and one of which rolls is supported at a higher level than the other, said rolls being positioned so that said threads pass over and part way around theupper roll and form a loop about the lower roll, and a thread support spaced laterally from the lower roll to hold the threads in. a looped condition about the lower roll, whereby each thread is free to sag away from'the lower tension regulating roll as it becomes slack and embraces this roll as it becomes taut, the arrange ment being such that the slack or taut condition of each thread controls independently of the other threads its gripping engagement with said rolls and the rate at which it is pulled forward 60 thereby.

2. In a machine of the class described, in com- -m bination, mechanism fordrawing forward simultaneously a number of threads, means for equalizing the tension of the individual threads sup- 65 plied to said mechanism including a pair of power driven tension regulating rolls spaced apart so that the threads may pass freely therebetween and positioned so that said threads pass part wayaround the first roll and form a loop about the .second roll, and a thread support positioned to hold the threads in a loope condition about said second roll, whereby eac thread is'free to sag away from the second roll as it becomes slack and embraces thisroll as it becomes taut, the

arrangement being such that the slack or taut condition of each thread controls independently of the other threads its gripping engagement with said rolls and the rate at which it is pulled forward thereby.

3. In a machine of the class described, in combination, mechanism for drawing forward simultaneously a number of threads, means for equalizing the tension of the individual threads supplied to said mechanism, including a pair of power driven tension regulating rolls spaced apart to provide a free thread passage between them and positioned so that said threads pass part way around the first roll and are looped about the second roll, and a thread support positioned to hold the threads in a looped condition about said second roll, whereby each thread is free to sag away from the second roll as it becomes slack and islbrought into embracing contact with said roll as it becomes taut, the arrangement being such that the slack or taut condition of each thread controls independently of the other threads its gripping engagement with said rolls and the rate at which it is pulled forward thereby.

4. In a machine for equalizing the tension of a number of threads arranged side by side, in combination a pair of power driven tension regulating rolls spaced apart so that the threads may pass freely therebetween and positioned so that said threads pass part way around the first roll and form a loop about the second roll to be frictionally pulled forward by these rolls, and a thread support positioned to hold the threads in a looped condition about said second roll, whereby each thread is free to sag away from the second roll as it becomes slack and embraces this roll as it becomes taut, the arrangement being such that the slack or taut condition of each thread controls independently of the other threads its gripping engagement with said rolls I and the rate at which it is pulled forward thereby.

5. In a machine for equalizing the tension of a number of threads arranged side by side, in combination a pair of power driven tension regulating rolls spaced apart so that the threads,

may pass freely therebetween andpositioned so that said threads pass part way around the first roll and form a loop about the second roll to be frictionally pulled forward by these rolls', a thread support positioned to hold the threads in a looped condition about said second roll, whereby each thread is free to sag away from the second roll as it becomes slack and embraces this roll as it becomes taut, the arrangement being such that the slack or taut condition of each thread controls independently of the other threads its gripping engagement with said rolls and the rateat which it is pulled forward thereby, and means for supporting one roll for adjustment about the axis of the other roll to thereby vary their frictional engagement with saidthreads.

6. In a machine for equalizing the tension or a number of threads arranged side by side, in combination, thread advancing mechanism, a pair of power driven rolls supported in spaced relation to each other between said mechanism and the source of thread supply and operable to ,frictionally pull the threads forward, said threads being looped about one roll in one direction and about the other roll in the opposite direction, and a support for supporting the threads looped about the latter roll so that each thread is free to sag away from the latter roll as it becomes slack and embraces this roll as it becomes taut,

pass freely therebetween and positioned one above the other and so that said threads pass part way around the first roll and form a loop about the second roll to be frictionally pulled forward by these rolls, a thread support positioned to hold the threads in a looped condition about said second roll, whereby each thread is free to sag away from the second roll as it becomes slack and embraces this roll as it becomes taut, the arrangement being such that the slack or taut condition of each thread controls independently of the other threads its gripping engagement with said rolls and the rate at which it is pulled forward thereby, and means for supporting one roll so that it maybe swung bodily about the other sufficiently for the threads to pass in a straight line therebetween in threading up the machine.

8. In a machine for equalizing the tension of a number of threads arranged side by side, in combination, a pair of friction pull rolls, means for supporting one of said rolls for adjustment support for supporting the threadslooped about the latter roll so that each thread is free to sag away from the latter roll as it becomes slack and embraces this roll as it becomes taut, the arrangement being such that the slack or taut condition of each thread controls independently of the other threads its gripping engagement with said rolls and the rate at which it is pulled forward thereby, and means for securing said roll supporting means in difierent positions of angular adjustment to vary the frictional pulling action of saidrolls. a

9. In a machine for equalizing the tension of a number of threads arranged side by side, in combination, a pair of friction pull rolls, spaced brackets for supporting one of the rolls therebetween for swinging movement about the axis of the other roll, a toothed locking member rig-' idly secured to each bracket, locking means engageable with the teeth of said locking members to lock the brackets in the desired position of angular adjustment so that said threads may be looped about one roll in one direction and about the latter roll so that each thread is free to sag away from this roll as it becomes slack and embraces this roll as it becomes taut, the arrangement being such that the slack or taut condition of each thread controls independently of the other threads its gripping engagement with said rolls and the rate at which it is pulled forward thereby.

10. In a machine for equalizing the tension of a number of threads arranged side by side, in combination, a. pair of friction pull rolls, spaced brackets for supporting one of the rolls therebetween for swinging movement about the axis of the other roll, a toothed locking member rigidlg secured to each bracket, a lock bolt for each toothed locking member to secure said brackets in the desired positidn of angular adjustment so that said threads may be looped about one roll in one direction and the other roll in the opposite direction,means for supporting the threads looped about the latter roll so that each thread 11. In a machine for unwinding elastic threads simultaneously from a number of spools and for equalizing the tension of these threads, in combination, a pair of friction pull rolls spaced apart.

so that the thread may pass freely therebetween, means for driving said folls, said threads being looped about one roll in one direction and about theother roll in the opposite direction, a support for supporting the threads looped about the latter roll so that each thread is free to sag away from the latter roll as it becomes-slack and embraces this roll as it becomes taut, the arrangement being such that the slack or taut condition of each thread controls independently of the other threads its gripping engagement with said rolls and the rate at which it is pulled forward thereby.

RAYMOND S. FRANUIS. 

